Download this free 2d cad block of a typical slate change of roof pitch detail including annotations and dimensions.
Slate roof pitch change.
A couple of likely slate suppliers are consulted and they confirm that they are happy to supply 600x300mm slates for a minimum roof pitch of 20 degrees assuming a minimum lap of 125mm.
Following the successful test results we are happy to advise specifiers and contractors that they can choose a siga natural slate roof as low as 15 degrees sheltered or moderate exposure and 17 5 degrees severe exposure if the slates are hook fixed with a 150mm lap.
It is agreed that the roof pitch should be a minimum of 20 degrees preferably a bit more.
The slope of a roof is often referred to as the roof s pitch.
You consider some alternative solutions.
This autocad detail can be used in your roof design cad drawings.
Traditionally a minimum roof pitch of 20 was recommended in bs 5534 but modern tiles and slates have now been designed for applications as low as 15.
Generally a slate roof is not installed on a pitch less than 4 12.
As per the nrca roofing and waterproofing manual fifth edition they recommend that roof deck slopes intended for the application of steep slope materials at 4 12 18 degrees or greater page 405.
A dramatic change in pitch will affect the way the roof looks the way water runs off of it and much more.
Even a slight change in pitch can have a variety of consequences depending on the roof.